I just received the PanzerArt M113 wheels today and they look great! Easily WAY better than any earlier M113 family kit wheels out there, maybe with exception of new AFV Club kit. Details are excellent and in scale, casting clean and molding blocks small and easy to remove.
There are two minor "issues". One is actually a result of very accurate dimensions - the outer and inner wheels are so close that guide horns of some older tracks may not fit without thinning them or adding thin distance rings between wheels.
The other issue is a small inaccuracy in PanzerArt wheels - in real wheels the rivets are on a small "bulge". It is represented - and actually slightly overdone - in the new AFV Club kit, but missing in PanzerArt wheels. But compared to all other kit wheels, the PanzerArt's are huge improvement.
Also the rivets and wear ring are not represented on the rear side of the wheels, but considering how close the wheels are, those details would not be visible anyway, so it's not a problem at all in my opinion.
This photo from PrimePortal shows the "bulge" under rivets:
Oups, I just noticed another issue in PanzerArt wheels - there are correct 8 bolts on the outer wheel, but 10 bolts on the inner wheel! To be honest, I don't care

Yes, but it creates the illusion of the "bulge", or additional convex ring.
They are undercut, but the undercut profile is not as deep as it should be to be 100% accurate. I'm not sure if fully correct undercut would be achievable for one piece resin part. I doubt the silicon mold would survive removal of the part. I guess that's why PanzerArt made it shallower than it should be. But it is certainly there.